Comparative characterization of the cell composition and functional properties of anti-CD19 biomedical cell products manufactured using the CliniMACS Prodigy and G-Rex platforms

Abstract

Today, the use of anti-CD19 biomedical cell products (BMCPs) for the treatment of B-cell malignancies yields impressive results and is becoming ever more popular. Several bioreactors have been developed that allow the manufacturing of high-quality cell products for clinical use. Choosing an appropriate bioreactor is an important step in this process. The aim of this study was to characterize and compare immunophenotypic and functional properties of anti-CD19 BMCPs manufactured using the automated CliniMACS Prodigy system (Miltenyi Biotec, Germany) and the manual G-Rex 10M-CS platform (Wilson Wolf, USA). The manufacturing of BMCPs and subsequent CAR T-cell therapy were carried out at the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology of Ministry of Healthcare of Russia. We used T cells from patients who had undergone HSCT as well as from autologous and allogeneic donors. In this study, we employed 26 anti-CD19 BMCPs manufactured using the automated CliniMACS Prodigy system in accordance with the GMP requirements as well as 25 cell products produced with the G-Rex platform. The study was approved by the Independent Ethics Committee and the Scientific Council of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology and Immunology. Quality control was ensured throughout the entire manufacturing cycle and included assessment of cell composition and survival, transduction efficiency, cell expansion, expression of exhaustion markers, and CD19-specific antitumor activity. Our research showed that both manufacturing platforms generate stable high-quality products with sufficient cell expansion, viability and T cell transduction for subsequent CAR-T therapy. However, the median transduction efficiency of the BMCPs produced using the CliniMACS Prodigy platform was statistically significantly higher than that of the BMCPs manufactured using the G-Rex bioreactor (41% vs 26%). The study showed that in the anti-CD19 BMCPs, there was a predominance of Tcm subpopulation over Tem subpopulation, a low expression of exhaustion markers and a pronounced CD19-specific activity. Nevertheless, the percentage of Tcm cells in the BMCPs manufactured using the CliniMACS Prodigy platform was statistically significantly higher than in the BMCPs produced using the G-Rex bioreactor (86.7% CD8+ Tcm cells and 82.3% CD4+ Tcm cells for CliniMACS Prodigy vs 69.0% CD8+ Tcm cells and 72.0% CD4+ Tcm cells for G-Rex). Despite the lower number of anti-CD19 CAR-T cells in the final cell products obtained with the G-Rex bioreactor, in all processes this amount was sufficient for subsequent CAR-T therapy. Thus, the CliniMACS Prodigy and G-Rex platforms can be used to produce high-quality anti-CD19 BMCPs.